The present invention relates to generally a memory controlled manipulator apparatus capable of repetitively performing reproducible operations, and more particularly to a digital position instruction or command signal modification device for use with a memory controlled manipulator apparatus, which may modify some or all of the digital position instruction or command signals stored in a memory without repeating the manual teaching operation, merely by setting or entering desired modifying values.
In order to enable a manipulator device to perform a desired series of programmed operations in succession during the repetitive working cycles, the manipulator is manually and sequentially displaced during the teaching operation from one desired position to another according to the desired series of operations to be performed, so that digital position signals representing the desired positions of the manipulator may be stored in a memory. Instruction signals for peripheral equipment for enabling various operations to be performed in cooperation or synchronism with the manipulator are simultaneously in the memory with operation instruction signals such as the driving speed instruction signals for the manipulator. In repetitive working cycles, the digital position signals and other various instruction signals stored in the memory are sequentially read out so that the manipulator may perform the desired series of operations. In the operation of manipulator apparatus of the above type, it is necessary to modify some or all of the digital position instruction signals stored in the memory when the actual position of the manipulator deviates from a programmed position or when the position of the manipulator with respect to an article to be handled by the manipulator is changed. For this purpose, the new teaching operation must be performed in the conventional manipulator apparatus, resulting in the considerable loss in time.